Richmond police Sgt. Michael Wang pulled his silver Mercedes-Benz 430 SUV into the Vallejo motel parking lot, stopping when his driver’s side window lined up next to the drug trafficker’s.

It was how he always parked during their secret meetings, the drug dealer, Sergio Vega-Robles, told Contra Costa investigators.

Vega-Robles jumped into Wang’s SUV, assured the officer he wasn’t wired or followed, and handed him a plastic bag filled with $20 bills in $1,000 rubberbanded stacks. It was 2004, and Wang was receiving the first of three $40,000 bribes from the drug informant.

Vega-Robles made those assertions and more in a lengthy Feb. 14 interrogation, spending almost three hours detailing accusations of a rogue drug cop to district attorney inspector John Conaty. This newspaper obtained the recorded video copy of the interview, which paints the picture of a vice officer infiltrating a drug dealer’s business to bust some West Contra Costa bad guys and quickly getting too close, eventually spiraling out of control.

Vega-Robles, 34, was offered immunity for his cooperation and testimony against prison gang founder Coby Phillips, who was indicted on murder, attempted murder and drug conspiracy charges. As Vega-Robles discussed the Phillips case, he began sharing more and more information about Wang, who now is under investigation.

In addition to the bribes, Vega-Robles told prosecutors that Wang tipped him off to a federal drug agency’s tracking device on his car and a gun sting, which led to the shooting of a police informant. Wang set up a drug deal and even dated the drug trafficker’s cousin, Vega-Robles told authorities.

As a result of the assertions, Wang, an 18-year veteran and personnel and training supervisor, was placed on paid administrative leave earlier this year while local and federal investigations continue. Richmond police Chief Chris Magnus has said his department is cooperating with those inquiries, saying he’s aware of “a number of serious and potentially criminal allegations.”

Richmond police Capt. Bisa French said last month that Wang remains on paid leave pending the results of the department’s investigation and, therefore, she could not comment further.

Wang’s attorney Harry Stern, who has not viewed the video, denied the accusations against his client.

“Mike Wang is a great cop. I haven’t heard anything that leads me to believe for one millisecond that he did anything wrong,” Stern said. “I still remain absolutely convinced these allegations are a smoke screen and a fantasy and nothing else.”

Vega-Robles had faced charges similar to those of his brother, who was sentenced last year to 75 years to life in prison for operating a major Bay Area methamphetamine ring and the 2004 murders of two drug associates in West Contra Costa. The murder charges against Vega-Robles were dropped upon his cooperation with prosecutors. Vega-Robles denied an interview request with this newspaper from his Contra Costa jail cell and his attorney declined to comment, but here’s his story, according to the two-hour, 50-minute interview:

Bribes

Vice officers often forge relationships with drug dealers in order to get tips and solve crimes. As a narcotics officer in Richmond, Wang, at least initially, was no different. A fellow drug dealer introduced Vega-Robles to Wang in 2002, telling the drug trafficker that the Richmond police narcotics officer, who worked with the West County Drug Enforcement Agency task force, would fix his immigration status in exchange for some street intelligence.

Wang introduced Vega-Robles to Gina Giachetti, his DEA partner. The dealer worked five cases with her from 2003 to 2005, hoping to get his green card.

Soon, Wang gave him his first assignment. Vega-Robles said he helped bust two drug dealers from Los Angeles: Tweety and Tacho. Wang had Vega-Robles buy 12 kilos of cocaine in three deals, paying $13,000 for each package. In an early sign of Wang crossing the line, Vega-Robles said Wang allowed him to sell each of the three coke orders and keep the $50,000 proceeds from each.

On the fourth deal, drug agents arrested Tacho, while Tweety escaped to Mexico.

A month later, Vega-Robles offered Wang the first $40,000 bribe.

“I was making much more money than $40,000, and I was happy and I wanted him to be happy, too,” Vega-Robles told investigators. “He was helping me a lot back then. He was giving me information about people. … I thought he was having my back, like, real tight.”

Wang declined at first, but not for long, Vega-Robles said. The pair met in 2004 at the Vallejo motel.

“I told him I was going to give him $40,000 every six months. He kind of, like, told me he would protect me in Richmond,” Vega-Robles said. “‘When you’re in Richmond, you’re OK. No problem. You can do whatever you want.'”

Deeper

As their partnership went further astray from the law, Vega-Robles said the two became closer.

They talked daily, sometimes by cellphone, and often they met in secret spots, such as behind the Levitz furniture store in El Sobrante. Vega-Robles said he would provide narcotics intelligence, and every once in a while Wang would provide him a favor, like the time he ran the serial number of a 9 mm handgun Vega-Robles bought. Wang told him it was reported lost in Livermore. Vega-Robles also would ask Wang to run license plates.

After accepting $120,000 in bribes, Vega-Robles said Wang began to take part in drug deals.

One day, at Wang’s request, the drug trafficker drove the vice cop to Elk Grove as part of a drug deal Wang set up with Anthony “Peanut” Hollingsworth. When they arrived at the house, Vega-Robles said he gave Wang $3,600, watched the officer enter the dealer’s house and come back with 3 pounds of ephedrine stuffed into a plastic food-storage container. On the drive back, the pair parked at a Walmart in Dixon, and Wang bought a new container for the drugs, keeping the old one so his fingerprints weren’t on the package.

Vega-Robles said he sold the drugs in Richmond, and Hollingsworth later told him he gave Wang $800 for setting up the deal.

Shooting

By 2005, Wang’s allegiance to his drug-dealer friend had begun undermining Richmond police and their associates, Vega-Robles said.

Wang tipped off Vega-Robles that his brother and cousin were about to buy guns from a Richmond police informant and risked getting arrested, the dealer said. The information kept Vega-Robles’ family members out of jail, but the revelation apparently got the informant shot shortly thereafter. He survived.

As federal officials began focusing on Vega-Robles’ circle, his cousin’s Jeep Cherokee was pulled over and impounded. Federal investigators placed a tracking device on it.

Vega-Robles said he got a call from Wang, and they met in person; the officer told him of the device. Vega-Robles alerted his cousin, and the pair crawled under the SUV with a flashlight and found a black box with an antenna sticking out. They took it off, cut the antenna and threw it into Mare Island Strait.

Vega-Robles said he eventually met Wang in the Richmond Police Department parking lot, and the officer showed him an arrest warrant for his brother on murder charges and more.

“He told me to tell my brother to go to Mexico,” Vega-Robles said.

Dating

The pair’s relationship turned bizarre when Wang started dating Vega-Robles’ cousin, who was living with the dealer’s family at the time. Wang would pick her up at Vega-Robles’ house for excursions.

The cousin eventually moved to Idaho, and Wang would visit her, paying her apartment’s rent for a year, Vega-Robles said. Wang even cooked a Thanksgiving dinner for the cousin’s parents in Boise.

She broke off the relationship due to Wang’s jealousy, Vega-Robles said.

In late 2005, Vega-Robles asked Wang to run the plate of a van that had been following him in Los Angeles for three days.

He said Wang told him: “You’re not hot, keep working.” It turned out to be federal officials, and he was arrested Nov. 30, 2005, eventually taking a plea deal on drug charges. He has been incarcerated ever since.

The drug dealer last spoke to Wang in 2011 while in jail. He said Wang visited him numerous times, telling him, “Don’t say nothing,” and he would make motions like “zip your lips shut.”

Vega-Robles finally went to the FBI and told them about the bribes, he said, after learning that Wang had been hitting on his wife while he was in jail.

Matthias Gafni is a Pulitzer Prize winning investigative reporter for the Bay Area News Group. He has reported and edited for Bay Area newspapers since he graduated from UC Davis, covering courts, crime, environment, science, child abuse, education, county and city government, and corruption. A Bay Area native, he loves his Warriors, Giants and 49ers. Send tips to 925-952-5026 or mgafni@bayareanewsgroup.com. Send him an encrypted text on Signal at 408-921-8719.